Terms & Conditions

These Terms & Conditions govern access to and use of CDNsun's website, account, content delivery network (CDN), storage features and related services (together, the Services). They contain the Terms of Service, Acceptable Use Policy (AUP) and a separate Service Level Agreement (SLA) below.

CDNsun s.r.o. (CDNsun, we, us) is a company incorporated in the Czech Republic, company number 05745314, with its registered office at V zářezu 902/4, 158 00 Prague, Czech Republic. A Customer or you is the person or entity that creates an account, orders or uses a Service. If you act for an entity, you represent that you are authorized to bind it. A Consumer is an individual acting outside a trade, business, craft or profession; a Business Customer is any other Customer.

By selecting the account-creation button after these Terms have been made available on the registration form, you accept them for your free trial and subsequent use of the Services. The trial begins when the account is activated. Paid use begins only when you place and pay for an add-funds order, unless a separate written agreement provides otherwise. The current Terms are available on our website; later changes are governed by section 1.8. Merely visiting the public website does not make you a paying Customer, but the AUP applies to your use of the website. Mandatory rights under applicable law remain unaffected.

1. Terms of Service

1.1 Services and orders

An order, plan or written agreement accepted by CDNsun identifies the Services, prices and any specific features. We may decline a proposed order or new Service request for capacity, technical compatibility, security, fraud-prevention, legal-compliance or other legitimate operational reasons. If we collect payment for an order that we decline, we will refund that payment without affecting charges for Services already provided. We may use our own and contracted infrastructure to provide the Services. We determine the technical architecture and operational methods in our reasonable judgment. For capacity planning, performance, security, compatibility, legal compliance, network integrity or other legitimate operational reasons, we may change routing, CDN locations, suppliers, networks, software, configurations and other technical components. We will continue to meet our express contractual commitments; a materially adverse change to a Service is governed by section 1.8. Features described as beta, trial or free may change or end, subject to applicable law and any specific written commitment.

A feature described as unlimited is available for reasonable use consistent with the Service's intended purpose; it does not mean infinite technical capacity or unrestricted use. In particular, use must not materially disrupt or degrade the Services or other users. Any proportionate operational measures for excessive load are governed by section 1.5.

The CDN caches and transmits content; its edge cache is not itself an archival or backup service. If a separate storage feature is ordered, it may be used as a CDN origin or for storage and backup purposes as described in its order and published technical documentation. Unless expressly agreed otherwise, CDNsun storage does not serve files directly to end users as a standalone public file-hosting service. CDNsun publishing point is for delivery through CDNsun's CDN, not for standalone public distribution to end users. Cache copies may be evicted or refreshed as part of ordinary CDN operation. Stored Customer Content may be lost, corrupted or unavailable because of incidents such as data-center fires, power failures or equipment failures. We do not guarantee against every such event, subject to our express commitments for an ordered storage feature and any liability that cannot lawfully be excluded. You are responsible for keeping independent copies of critical source content and for testing restoration. We do not promise that cached copies will be recoverable after loss of an origin or stored object.

1.2 Accounts and security

You must provide accurate account and billing information and keep it current. You are responsible for authorized users, account credentials and activity under your account, except to the extent caused by CDNsun's breach or by circumstances for which the law makes CDNsun responsible. Use appropriate security controls and promptly report suspected compromise to CDNsun support. We may require reasonable verification before changing account ownership, billing or security settings.

You must be legally capable of entering this contract. We may reject duplicate or abusive free-trial accounts and impose reasonable technical and anti-fraud limits disclosed with the trial.

1.3 Customer content and rights

Customer Content means content you submit, store, cache or deliver through the Services. You retain your rights in it and are responsible for having the rights and permissions needed to use it. You grant CDNsun and its service providers a worldwide, non-exclusive, royalty-free license, for the term of service and any technically necessary wind-down or legal retention period, to host, copy, cache, transmit, display and technically transform Customer Content solely as necessary to provide, secure, maintain and support the Services, comply with law, and carry out your instructions. This license does not transfer ownership or permit unrelated marketing use. You remain responsible for notices, permissions and lawful bases needed for your end users and content.

CDNsun retains its intellectual-property rights in the Services, software, documentation, trademarks and website. We grant you a limited, non-exclusive, non-transferable right to access and use the Services, software, documentation and website during your authorized use of the Services, subject to these Terms. No right to use CDNsun marks is granted except with written permission.

1.4 Prices, billing, taxes and prepaid balance

Prices, usage metrics, payment timing and any recurring or usage-based charges are those shown at order or agreed in writing. A Customer may add funds by creating and paying an order within the account. Unless stated otherwise, prices are in USD and exclude applicable taxes; the amount payable, including applicable taxes, is shown before payment. You are responsible for taxes properly chargeable to you, excluding taxes on CDNsun's income. After payment, we send confirmation by email and make the invoice available in the billing area. You must pay undisputed amounts when due and raise a billing dispute promptly with enough detail to investigate; you may not withhold unrelated undisputed amounts. We will correct billing errors that we verify.

If your account uses prepaid credit, charges are deducted from its available balance. We may pause billable Services if the available balance is insufficient, after notice where reasonably practicable. Promotional credit may have separate disclosed conditions. Purchased prepaid credit expires 12 months after it is added; adding new purchased credit before expiry extends the expiry of the then-unexpired purchased balance to 12 months after the new addition. We will show or otherwise make the applicable expiry information available in the account or purchase process. Expiry never overrides mandatory refund, withdrawal or other Consumer rights.

If a payment used to fund your account is reversed, charged back or otherwise not received, we may adjust the available balance to reflect that payment. You remain responsible for valid charges for Services actually provided, including charges recorded after a metering delay that cause a negative balance. We may request payment of the resulting amount and pause further billable Services until the balance is restored or the payment issue is resolved, after notice where reasonably practicable. We will correct verified billing errors. This paragraph does not limit your right to dispute a charge or obtain a refund under applicable law.

An add-funds order purchases prepaid credit for future use of the Services. Payment for that order is final once processed; the invoice records the completed purchase. Purchased credit is non-refundable and cannot be cashed out, except where applicable law requires a refund or an accepted order expressly provides one.

1.5 Suspension and termination

We may proportionately suspend or restrict a Service when reasonably necessary to address a material AUP violation, a security threat, unlawful content, non-payment, fraud, a legal order, or a material risk to CDNsun infrastructure, other users or the network. Where practicable, we will give notice and an opportunity to cure before suspension; we may act immediately where reasonably necessary, including when delay would create material risk or be unlawful. We will restore access when the reason is resolved, if reasonably practicable. A suspension does not excuse payment for charges already incurred.

If a complaint or other information gives us reasonable grounds to suspect unlawful activity, infringement of third-party rights, a breach of this AUP or a material risk to others or the Services, we may immediately restrict or suspend the affected content, Service or account where reasonably necessary while we assess the matter. We will provide any notice or explanation required by law.

If we reasonably determine from the available evidence that a Customer's use of the Services is unlawful, infringes third-party rights, or involves a serious or repeated breach of the AUP, we may disable the affected content or Service, suspend or terminate the account, and reject new accounts or orders that we reasonably believe are intended to circumvent that action. We may act immediately without prior notice or an opportunity to cure where delay would allow the activity to continue or create material legal, security or operational risk. We will act proportionately where practicable and provide any notice or explanation required by law.

If we reasonably determine that a Customer's configuration, integration, traffic or use is causing material disruption, degradation or a security risk to our infrastructure or other users, including through excessive load, or have reasonable grounds to believe it is likely to do so, we may immediately rate-limit traffic, disable affected features, change the technical configuration, isolate resources or suspend the affected Service without waiting for an AUP violation. We may terminate the affected Service or account if the risk cannot reasonably be mitigated, continues or recurs after notice and a reasonable opportunity to remedy, or immediate termination is reasonably necessary to prevent serious harm. We will use measures proportionate to the risk where practicable.

Either party may terminate an affected Service or account for the other party's material breach if the breach is not cured within 15 days after written notice, unless it cannot be cured or immediate termination is legally justified. This cure period does not apply to CDNsun's immediate termination rights above. You may stop using a prepaid Service at any time, subject to section 1.4 and any agreed minimum term. We may discontinue a Service without Customer breach on reasonable advance notice, or sooner if continued provision is unlawful or impracticable for reasons beyond our reasonable control. We may terminate a trial or free account, whether active or inactive, on reasonable notice. Mandatory rights and remedies remain unaffected.

Before termination takes effect, you should export any content held in a storage feature using available tools. For Business Customers, we do not promise post-termination access or assisted export unless expressly agreed, required by an applicable data-processing agreement or required by law. Any mandatory Consumer right to retrieve content remains unaffected. Urgent security, legal or abuse circumstances may restrict access before termination. CDN edge caches are not an export or backup facility. After termination, we may delete or make inaccessible Customer Content in accordance with our operational and legal obligations and any applicable data-processing agreement. We make no fixed retention promise in these Terms. Accrued payment obligations, rights and provisions intended to survive termination remain in effect.

1.6 Privacy and data processing

Our Privacy Policy explains how we handle personal data as a controller. Our GDPR information describes data-processing roles and access to a data-processing agreement (DPA). Where a valid DPA applies, it governs processing of personal data on behalf of the Customer. These Terms do not replace that DPA or any consent or notice required under privacy law.

1.7 Warranties, risks and liability

We will provide the paid Services with reasonable care and skill and meet the express commitments in the applicable order and the SLA below. Except for those commitments and rights that cannot be excluded by law, we do not guarantee uninterrupted, error-free or universally reachable operation, any particular business result, or that every third-party network, origin, device or application will work with the Services. You are responsible for configuring a suitable origin, DNS, security rules and fallback arrangements for your own use case.

For Business Customers only, and to the maximum extent permitted by law, CDNsun is not liable to the Business Customer for lost profits, lost revenue, loss of business opportunity or indirect or consequential loss arising from the Services, even if advised of the possibility. This exclusion does not eliminate a direct loss merely because it involves data or business operations. Subject to the exceptions below, CDNsun's aggregate liability to a Business Customer for all non-SLA claims arising from an event or related series of events is limited to the greater of USD 100 or the fees paid or payable for the affected Services during the 12 months before the first event giving rise to the claim. This is one aggregate cap, not a separate cap per claim. The SLA's credit cap applies separately to SLA credits and does not reduce a remedy that cannot lawfully be limited.

Nothing in these Terms excludes or limits liability for intentional harm, gross negligence, harm to a person's natural rights, fraud, or any other liability that cannot lawfully be excluded or limited under Czech law or another mandatory applicable law. The exclusions and cap above do not restrict a Consumer's non-waivable rights or remedies. Nothing requires either party to waive a claim before the facts are known where such a waiver would be invalid. Each party must take reasonable steps to mitigate loss.

For Business Customers, the SLA credit is the sole contractual remedy for failure to meet the specific 99.9% CDN availability commitment, except for the non-excludable liabilities just described. It is not the sole remedy for a different breach of these Terms. For Consumers, the SLA credit is an additional contractual benefit and does not replace mandatory statutory remedies.

1.8 Changes to Terms, prices and Services

We may update these Terms, the SLA, prices or material Service features prospectively. We will give Business Customers reasonable advance notice of a material adverse change by email to the account's contractual contact or through an account notice reasonably likely to be seen, identifying the effective date and how to end the affected Service. For Consumers, we will provide the notice, information and rights required by applicable law, including reasonable advance notice on a durable medium where required. You may terminate the affected Service before that date without a new termination fee; any additional rights required by law remain unaffected. Changes required promptly by law, to address an urgent security risk, or to prevent material harm may take effect sooner; we will give notice as soon as reasonably practicable and provide any exit right required by law. Non-material clarifications may take effect when posted, with an updated effective date.

A change does not retroactively alter accrued rights, existing SLA claims or completed billing periods. For Business Customers, logging in to the account, using the Services or placing and paying an add-funds order after the properly notified effective date constitutes acceptance of the updated Terms. For Consumers, the same acts constitute acceptance only to the extent permitted by applicable law; if express consent is legally required, we will seek it. A separately signed agreement or order may require a different amendment process.

1.9 Consumers: withdrawal and disputes

Where a Consumer has a statutory right to withdraw from a distance or off-premises contract, the withdrawal period is generally 14 days from conclusion of the relevant service contract. A Consumer may withdraw by sending an unequivocal statement to CDNsun support or by using another contact method listed in section 4. The optional model statement below may be used. We will provide legally required information about any paid order before it is placed. We will make any refund due after valid withdrawal in the manner and time required by law.

Optional withdrawal statement: To CDNsun s.r.o.: I hereby withdraw from my contract for [service or order], concluded on [date]. My name and address are [name and address]. Date: [date].

If a Consumer expressly requests that service begin during the withdrawal period and then validly withdraws, any proportionate charge is due only where and to the extent applicable law permits. Beginning an ongoing CDN service does not by itself extinguish the withdrawal right. Any statutory exception for fully performed services applies only when its legal conditions, including any required express request and acknowledgment, are met. Mandatory rights concerning defective digital services, unfair terms or other consumer protections remain unaffected.

Please first contact CDNsun support so we can try to resolve a complaint. This does not limit access to a court or another competent body under mandatory law.

1.10 Governing law, jurisdiction and priority

Czech law governs these Terms, excluding its conflict-of-law rules, subject to mandatory law. For a Consumer, this choice does not deprive the Consumer of mandatory protections of the law of their habitual residence where applicable conflict-of-law rules provide them. Business Customers agree that courts competent for Prague, Czech Republic have exclusive jurisdiction, unless a mandatory rule provides otherwise. A Consumer may bring or defend proceedings in any court available under applicable mandatory jurisdiction rules; the Prague clause does not apply to Consumers.

If documents conflict, the following order applies, but only for the subject each document covers: (1) a mutually signed agreement expressly varying these Terms; (2) an accepted order or plan's specific commercial terms; (3) the SLA for its availability calculation and credit procedure; (4) these Terms of Service; and (5) the AUP. A DPA takes priority for processing of personal data on the Customer's behalf. The Privacy Policy remains a separate notice and does not change this order. A document has no priority over mandatory law. If any provision is unenforceable, the rest remains effective to the extent lawful.

2. Acceptable Use Policy (AUP)

You may use the Services only for lawful purposes and in a way that does not materially impair the Services or other users. You must comply with laws applicable to your content and use, including intellectual-property, privacy, export-control and sanctions laws.

You must not use the Services to distribute unlawful content; store, cache or deliver content without the rights or permissions required to do so; infringe another person's rights, including copyright; conduct fraud, phishing, malware distribution, credential theft or unauthorized surveillance; send abusive traffic or spam; attempt unauthorized access, scanning or exploitation; interfere with networks or other users; evade reasonable technical limits; or misrepresent your identity or authority. Security testing requires the relevant system owner's authorization and must not disrupt service. You must not use CDNsun storage as a standalone public distribution service where your order limits it to origin use for CDN delivery. You must not use CDNsun publishing point as a standalone public distribution service; end-user delivery of content sent to it must occur through CDNsun's CDN.

You are responsible for the Customer Content and your end users' activity through your account. You must respond reasonably to substantiated abuse reports and cooperate with lawful investigations. Report suspected abuse or security concerns to CDNsun support, identifying the relevant content or activity and basis for concern. We may investigate, request information, remove or disable access to specific content, rate-limit traffic, or suspend a Service as proportionately necessary. We will consider the nature of the report, available evidence, legal duties, risk of harm and your response; we do not promise to monitor all content or to resolve every complaint immediately. We may notify the Customer before action where lawful and reasonably practicable. We may preserve and disclose information only as permitted or required by law and applicable privacy commitments.

A Business Customer will indemnify CDNsun against third-party claims, damages, reasonable settlement amounts and reasonable costs, including legal fees, to the extent arising from Customer Content, the Customer's or its end users' use of the Services, or the Customer's breach of these Terms, except to the extent caused by CDNsun's own acts or omissions. CDNsun will give the Customer prompt notice of a claim and may control its own defense. The Customer will cooperate reasonably and may participate in the defense at its own expense. CDNsun will not settle a claim at the Customer's expense without the Customer's prior consent, not to be unreasonably withheld or delayed. This indemnity is not capped by fees paid for the Services and does not apply to Consumers.

3. Service Level Agreement (SLA)

3.1 Scope and commitment

This SLA applies to paid CDN delivery Services under an active account, unless an accepted order or signed agreement expressly substitutes another SLA. It does not apply to free trials, non-CDN services, origin storage availability or third-party services. CDNsun commits to 99.9% 30-Day CDN Availability for each individual paid CDN delivery Service identified in the Customer's account (the Affected CDN Service). Availability and charges are assessed separately for each Affected CDN Service. A failure affecting multiple CDN Services may be assessed for each, but the same charges may not be credited twice.

For each claimed incident, the 30-Day Measurement Period is the 30 consecutive 24-hour days ending when that incident ended, measured in UTC. If an incident is still ongoing when a claim is submitted, the period ends when the claim is submitted. Only minutes when the Affected CDN Service was active after the account was upgraded from the free trial and was not suspended are measured. For this SLA, an Eligible Minute is a one-minute interval in that period, excluding minutes affected by a section 3.4 exclusion. The denominator is the number of Eligible Minutes.

An Unavailable Minute is an Eligible Minute during which more than 50% of valid requests to the Affected CDN Service fail because CDNsun's CDN edge cannot serve or deliver them. A qualifying failure is a CDNsun-generated HTTP 500–599 response or edge-side connection or TLS failure documented by the Customer's server request logs and corroborated by CDNsun's available data. A valid request is one directed to a correctly configured Service with a reachable, functioning origin where origin retrieval is required, and not deliberately blocked by a Customer rule or an applicable exclusion. An origin-generated error passed through by the CDN is not a qualifying failure. A period with no qualifying logged requests does not establish an Unavailable Minute under this contractual SLA, including where the Customer reports a complete outage. Isolated errors below the majority threshold do not make the whole minute unavailable.

30-Day CDN Availability = 100 × (Eligible Minutes − Unavailable Minutes) / Eligible Minutes. If there are no Eligible Minutes or no charges for the Affected CDN Service in the 30-Day Measurement Period, no credit is payable. CDNsun will assess the required Customer server request logs against its available edge and network data. Tests or monitoring performed by the Customer, its vendors or partners do not, on their own, establish the length, type or extent of an Unavailable Minute for a contractual credit. CDNsun may verify the claim and reject errors it cannot reasonably corroborate. This evidentiary rule applies only to the contractual SLA credit and does not restrict a non-waivable statutory right.

3.2 Service credits

If 30-Day CDN Availability for an Affected CDN Service is below 99.9%, the Customer may claim a credit calculated on the 30-Day Affected CDN Charges: the metered CDN-delivery usage charges paid or payable for that Affected CDN Service in the same 30-Day Measurement Period, excluding taxes, storage, other add-ons, one-time fees and charges for unaffected Services. Purchased prepaid balance and promotional credit are not charges for this calculation; only actual usage of the Affected CDN Service counts. Credits do not apply to unpaid, disputed or fraudulent charges until the underlying charge is resolved.

No credit is due at or above 99.9%. All credits for the same Affected CDN Service and 30-Day Measurement Period are capped in total at 25% of 30-Day Affected CDN Charges, regardless of the number of incidents or claims. The same failed minutes and usage charges cannot support overlapping SLA credits or duplicate compensation under multiple SLA schedules. A credit is applied to future CDN-delivery charges on the same account; it is not a cash payment and is not transferable. An unused SLA credit expires 12 months after issuance, unless applicable law requires a different treatment. Credits do not reduce any mandatory Consumer remedy or other liability that cannot lawfully be limited.

3.3 Claims and verification

Submit a claim to CDNsun support with subject SLA Claim within 30 days after the end of the claimed incident. Identify the account, Affected CDN Service and incident's UTC start and end times. Provide Customer server request logs showing the qualifying errors and corroborating the claimed outage in the support case; redact confidential or sensitive information not needed to assess the claim. The claim and required logs must be received by the deadline. The deadline and log requirement are conditions for this contractual credit, not limits on non-waivable legal rights.

We will assess the required logs against our available data and may request additional information to verify the errors, timing, affected Service and applicable exclusions. Customer or third-party monitoring results do not replace the required logs. If eligible, we will apply the credit within a reasonable billing cycle after verification. No minimum dollar threshold applies.

3.4 Causal exclusions

The availability commitment does not apply to an interruption or performance issue arising from:

• scheduled or emergency maintenance, or an interruption requested by the Customer;
• factors outside CDNsun's reasonable control, including data-center fires or power failures, external Internet or access-network problems (such as terrestrial or submarine cable cuts), denial-of-service attacks and other force majeure events;
• any act or omission of the Customer or a third party outside CDNsun's direct control;
• Customer equipment, software, origin, DNS, certificates, application, configuration, traffic controls or failure to maintain a functioning origin where needed;
• third-party equipment, software or technology outside CDNsun's direct control; or
• suspension or restriction permitted by these Terms, including for non-payment, security or violation of the AUP.

CDNsun may determine from the available evidence whether an exclusion applies. A Customer may submit contrary evidence for review, but customer or third-party tests alone do not establish entitlement to a contractual credit. CDNsun may, at its discretion, issue a credit for an event outside this SLA without creating a continuing obligation to do so. These exclusions do not limit non-waivable statutory rights.

3.5 Relationship to other rights

For Business Customers, service credits are the sole contractual remedy for breach of the 99.9% 30-Day CDN Availability commitment, subject to the non-excludable liability exceptions in section 1.7. They do not excuse payment obligations or bar claims for a different breach. For Consumers, service credits are additional to, and do not replace or cap, mandatory remedies under applicable consumer law. This SLA does not promise uninterrupted service or a particular recovery time.

4. Contact

Use our contact form to reach CDNsun support. You can also use the helpdesk or these email addresses: info@cdnsun.com for account, billing and legal matters; support@cdnsun.com for support and SLA claims; and abuse@cdnsun.com for abuse reports. Written notices may be sent to CDNsun s.r.o., V zářezu 902/4, 158 00 Prague, Czech Republic. We may send contractual notices to the account contact you maintain with us.

For consumer disputes within its competence, the out-of-court dispute-resolution body is the Czech Trade Inspection Authority.

What next?

Read about the following topics.

• Privacy Policy
• General Data Protection Regulation (GDPR)